> For the complete documentation index, see [llms.txt](https://support.emarketeer.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://support.emarketeer.com/references/developer-advanced/dcl-introduction/language-syntax.md).

# Language Syntax

The example below prints the firstname from the contact card.

```
<% contact field="firstname" %>
```

| Token         | Meaning                                    |
| ------------- | ------------------------------------------ |
| `<%`          | Tells the page a DCL function is starting. |
| `contact`     | The name of the function.                  |
| `field`       | The argument name.                         |
| `"firstname"` | The argument value.                        |
| `%>`          | Ends the DCL function.                     |

## Whitespace

Whitespace characters are not visible and can be used freely to keep your DCL code readable. You can write the same function like this:

```
<%
contact
field="firstname"
%>
```

This is more useful when DCL lines become long.

## Functions

A function starts with `<%` and ends with `%>`. It returns a string that is printed on the page or used as an argument to another function. The example below builds a link to your website using the user field `website` as an argument to the `link` function.

```
<% link url=<% user field="website" %> caption="Link to Website" %>
```

## Strings

A string is a sequence of zero or more characters. In DCL, a literal string is written with double quotes.

```
"This is a string"
```

Only one character needs to be escaped in a literal string: the double quote. Two double quotes in a row produce one double quote in the resulting string.

```
"There is only 1 "" in this string"
```

Concatenate strings with the `+` character.

```
"This is a string" + "We add this string"
```

Because functions return strings, you can pass a function as an argument to another function, and you can concatenate functions and literal strings. The example below takes firstname and lastname from the contact card, puts a space between them, and uppercases the result. Whitespace is used to keep the code readable.

```
<% upper string=
	<% contact field="firstname" %> +
	 " " +
	 <% contact field="lastname" %>
%>
```


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